#include<iostream>
#include<string>
#include<map>
using namespace std;
string s, name;
map<string, int>mp;
int main()
{
	int n;
	cin >> n;
	getline(cin, s);
	while (n--) {
		getline(cin, s);
		string temp = "";
		for (int i = 0; i < s.size(); i++) {
			while (s[i] != ' ') {
				temp += s[i];
				i++;
			}
			mp[temp]++;
			if (s[i] == ' ') {
				break;
			}
		}
	}
	cin >> name;
	if (mp[name] >= 3) {
		cout << "yidashan!" << endl;
	}
	else {
		cout << "kexi" << endl;
	}
	return 0;
}